1. Field of the Invention
The present invention relates to an oil-cooler-equipped radiator in which an oil cooler is fixed in a radiator by brazing while the oil cooler is accommodated in a tank of the radiator for a motor vehicle, and others.
2. Description of the Related Art
Hitherto, techniques about an oil-cooler-equipped radiator in which an oil cooler is accommodated in a tank of the radiator have been known. Examples of such oil-cooler-equipped radiators are disclosed in Japanese Patent Applications Laid-open No. 2001-153586 and No. Hei 10-73393.
Also, an all-aluminum radiator in which the tank and core part of the radiator are made of aluminum has been developed in recent years. In this type of radiator, brazing of an oil cooler and a tank of the radiator is performed while the oil cooler made of aluminum is accommodated in the tank.
Referring to FIG. 11, when a conventional oil cooler is to be brazed alone, a plurality of plates 102 are pressed toward the center of the stacking direction (in the directions indicated by the arrows in FIG. 11) by using platy jigs 101. In this way, the oil cooler 103 is temporarily assembled, with no gaps existing between the components thereof, and then the oil cooler 103 is brazed in a heating furnace, not shown.
However, in order to perform brazing of the oil cooler and a tank of the radiator while the oil cooler is accommodated in the tank, jigs for temporarily assembling the oil cooler and the tank are necessary in addition to the platy jigs 101 shown in FIG. 11. Further, these jigs must be removed from the radiator and the oil cooler after the brazing.
Also, in the above-described known art, a brazing process is performed in a state where both oil connecting pipes of the oil cooler, which are disposed through holes in the side wall of the tank of the radiator, are fixed to the side wall of the tank of the radiator, whereby the following problems to be solved arise.
That is, as it is difficult to evenly transfer heat to the oil cooler in the tank during a brazing process, the temperature difference between the side wall of the tank and the oil cooler inside the tank causes a difference in thermal expansion therebetween. As a result, deformation may occur in the oil cooler and/or the side wall of the tank, or brazing failure may occur disadvantageously.
If a time period of brazing in a heating furnace is extended to decrease the temperature difference, zinc diffusion in a radiator tube proceeds while degrading the corrosion resistance of the radiator tube, which is unfavorable.
The present invention has been made in view of the above-described problems, and it is an object of the present invention to provide an oil-cooler-equipped radiator in which an oil cooler can be heat-treated together with the radiator while the oil cooler is accommodated in a tank of the radiator so that each component of the oil cooler can be brazed at the same time, without performing a troublesome operation of removing jigs used for temporary assembling and without causing deformation of each member due to heat treatment or brazing failure.